Re: reverse a list. is this a good solution

Hi,

It is indeed a good way to solve it since it's tail recursion, however,
there's one more thing to do to make it easier, wrap it with a more
convenient function:

let rev_list_tail_rec l =
  let rec aux_rev l accum =
    match l with
    | [] -> accum
    | h :: tl ->
      aux_rev tl (h::accum)
  in
  aux_rev l []

this way, you can just use rev_list_tail_rec l instead of having to give
one more [] as the initial value of the accumulator.

2014-10-20 18:56 GMT+08:00 Roelof Wobben [email protected] [ocaml_beginners]
<[email protected]>:

>
>
> Hello,
>
> I try the 99 ocaml problems and have solved the reverse a list problem.
>
> My solution looks like this :
>
> let rec test l1 l2 =
> match l1 with
> | [] -> l2
> | h :: t -> test t (h::l2)
> ;;
>
> Is this a good way to solve it or are there things that can be better ?
>
> Roelof
>
>  
>



-- 
曹竞帆
哈尔滨工业大学计算机科学与技术专业本科在读
哈尔滨工业大学IBMTC成员